1. Field of the Invention
The present invention relates to a package for electronic components.
2. Background Arts
Electronic components such as semiconductor devices, capacitors, and so on are enclosed within a package of an electronic device. The electronic components are mounted on a metal base comprising the package and enclosed air-tightly by a casing and a lid surrounding and covering the electronic components. Lead terminals, which electrically connect the electronic components within the package to the outside, pass through the casing also mounted on the metal base as putting insulating feedthrough against the metal base to be electrically isolated from the base.
In an application of the electronic device, namely, putting the electronic device in a high vacuum and inputting/outputting a high frequency signal having extremely large power to/from the electronic components through the lead terminals, a vacuum discharge called as the multipactor discharge possibly occurs between the lead terminal and the metal base. When the high frequency signal is constant in the frequency and the power thereof, the possibility to induce the multipactor discharge depends on a distance between the lead terminal and the metal base. One prior document has reported to take a distance from the lead terminal to the metal base longer than 1 mm. However, the feedthrough put between the lead terminal and the metal base usually determines the distance therebetween, and a thicker feedthrough possibly brings the failure of the air-tightness of the package.